1. Field of the Invention
The invention concerns the area of conveying and handling objects, in particular printed objects and supplements. It relates to a method, a computer program system and a control system for the control of an installation for the gathering of flexible individual products.
2. Description of the Related Art
When products are collated in the printing industry, a pre-determined selection of products is gathered in a collection and this collection is further processed. Therein employed are e.g. gatherer-stitchers for periodicals, inserting drums for newspapers and other gathering machines for bookbinding. A collection comprises e.g. the following individual products: a periodical, several advertising brochures, a flatpack toy supplement, and a personalized address sheet. In the subsequent processing the collection is e.g. foil wrapped.
The individual products or part products are typically flexible, flat and/or thin, and are directed by associated means of supply into a gathering machine. There a collection is formed e.g. by superposing the individual products on to a clocked product stream. According to the state-of-the-art technology a faultless functioning of the means of supply is of great importance, ensuring that every collection comprises the correct composition, i.e. receives all the required part products. To warrant this, e.g. a particular means of supply is monitored to ascertain its correct functioning, in particular whether it actually puts an individual product into the collection at a specified clock speed. If this is not the case, the incomplete collection is discharged or segregated, in other words removed, rejected or released, prior to further processing. If several individual products repeatedly fail to be supplied, the gathering machine may be switched off or reset. Alternatively, a primary means of supply with important or critical individual products can be provided with a backup means of supply, which inserts the missing individual product during the temporary failure of the primary means of supply. Thus a high quality of collection is guaranteed, this however requires a large expenditure of machinery, the production is slowed down, or requires a laborious process of processing the segregated collections.
In the case of non-critical individual products such a control may not be necessary. Thereby it is accepted, however, that one or several individual products are missing in an unknown or uncontrollable quantity of collections.